lib/PublicInbox/Git.pm | 4 +---
 t/run.perl             | 4 ++--

diff --git a/lib/PublicInbox/Git.pm b/lib/PublicInbox/Git.pm
index 219a173246a8cc08e197b45691a7427cee71e2a9..5ef1db2f8c5da5fd94bf70e57255173f0ba16e3c 100644
--- a/lib/PublicInbox/Git.pm
+++ b/lib/PublicInbox/Git.pm
@@ -27,9 +27,7 @@ our $PIPE_BUFSIZ = 65536; # Linux default
 our $in_cleanup;
 our $RDTIMEO = 60_000; # milliseconds
 
-use constant MAX_INFLIGHT =>
-	(($^O eq 'linux' ? 4096 : POSIX::_POSIX_PIPE_BUF()) * 3)
-	/
+use constant MAX_INFLIGHT => (POSIX::PIPE_BUF * 3) /
 	65; # SHA-256 hex size + "\n" in preparation for git using non-SHA1
 
 my %GIT_ESC = (
diff --git a/t/run.perl b/t/run.perl
index 5082125bab6e609711089d2aff3649a513fed474..b0ee611a44626184cf8db19c4f781b620cad6be9 100755
--- a/t/run.perl
+++ b/t/run.perl
@@ -18,7 +18,7 @@ use PublicInbox::Spawn;
 use Getopt::Long qw(:config gnu_getopt no_ignore_case auto_abbrev);
 use Errno qw(EINTR);
 use Fcntl qw(:seek);
-use POSIX qw(_POSIX_PIPE_BUF WNOHANG);
+use POSIX qw(WNOHANG);
 use File::Temp ();
 my $jobs = 1;
 my $repeat = 1;
@@ -199,7 +199,7 @@ 	# had broken read(2) semantics according to the read(2) manpage
 	pipe(my ($rd, $wr)) or DIE "pipe: $!";
 
 	# fill the queue before forking so children can start earlier
-	my $n = (_POSIX_PIPE_BUF / UINT_SIZE);
+	my $n = (POSIX::PIPE_BUF / UINT_SIZE);
 	if ($n >= $#todo) {
 		print $wr join('', map { pack('I', $_) } (0..$#todo)) or DIE;
 		undef $wr;